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Demser Side Effects

Generic Name: metyrosine

Note: This document contains side effect information about metyrosine. Some of the dosage forms listed on this page may not apply to the brand name Demser.

Applies to metyrosine: oral capsule

Along with its needed effects, metyrosine (the active ingredient contained in Demser) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur while taking metyrosine:

More Common

  • Diarrhea
  • drooling
  • trembling and shaking of hands and fingers
  • trouble in speaking

Less Common

  • Anxiety
  • confusion
  • hallucinations (seeing, hearing, or feeling things that are not there)
  • mental depression

Rare

  • Black, tarry stools
  • blood in urine or stools
  • unusual bleeding or bruising
  • muscle spasms, especially of neck and back
  • painful urination
  • pinpoint red spots on skin
  • restlessness
  • shortness of breath
  • shuffling walk
  • skin rash and itching
  • swelling of feet or lower legs
  • tic-like (jerky) movements of head, face, mouth, and neck
  • unusual tiredness or weakness

Some side effects of metyrosine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More Common

  • Drowsiness

Less Common

  • Decreased sexual ability in men
  • dryness of mouth
  • nausea, vomiting, or stomach pain
  • stuffy nose
  • swelling of breasts or unusual milk production

After you stop using this medicine, it may still produce some side effects that need attention. During this period of time, check with your doctor immediately if you notice the following side effects:

More Common

  • Diarrhea

Also, after you Stop taking metyrosine, you may have feelings of increased energy or you may have trouble sleeping. However, these effects should last only for two or three days.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

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